293 



spray " may be used in conjunction with Vermorel's colloidal-soap 

 spray. To prepare the latter, dissolve 1 part of copper sulphate in 

 250 parts of water ; dissolve 1 part of white, alkali-free, olein soap in 

 250 parts of water ; finally pour the copper solution into the soap 

 solution, contrary to the usual procedure. An opaque, green or greeny 

 blue liquid is obtained, which wets the grapes effectively. The above 

 two formulae are given with reference to the control of mildew. 



Carle (G.). La Lutte contre les Sauterelles. [Control measures 

 against Grasshoppers.] — Bull. Econ., de Madagascar et Depen- 

 dances, Tananarive, nos. 3-4, January 1915, pp. 243-246. 



The collection of information relating to control measures against 

 grasshoppers, which have been tried in Madagascar, has been undertaken 

 by the Colonisation Department and is partly published here. Various 

 methods have been tried : burning, collecting, crushing, burying in 

 trenches and poisoning. Poisoning has been tried in two districts, 

 Ambanja and Ambilobe, the work having been started at the beginning 

 of December and being still in progress. In Ambanja, the workers are 

 satisfied that the poison does not instantly kill the insects, but 24 hours 

 later the swarm was completely poisoned. In Ambilobe, 50-70 per 

 cent, of the swarms operated on were poisoned, though it is noted that 

 the effect of the poisoning was not observed 24 hours after the operation. 

 It is considered advisable to return to mixtures of arsenicals with 

 sugar solution or molasses ; if sugar is not added, the grasshopper 

 eats the moistened vegetation only when driven by hunger. Among 

 other methods, a mixture consisting of 1 part petroleam to 10 parts 

 water is said to have been successful. This method should be further 

 tested, though necessarily costly, 22 gallons costmg 6s., as compared 

 with Is. l^d. for sodium arsenite. It is suggested that the neighbour- 

 hood of Antananarivo affords a good place for experimentation with 

 Coccobacillus acridiorum. It is considered that the trench method, 

 especially where labour is plentiful, is the simplest and the most likely 

 to be generally adopted, while poisoning is advisable in sparsely 

 populated regions. It is, however, emphasised that far more 

 important than the choice of a method is a comprehensive organisation 

 for the encouragement and reward of all who detect and inform the 

 authorities of the presence of eggs or of swarms, and suggestions for 

 this purpose are made. 



Caesar (L.) & Spexcer (G. J.). Cherry Fruit-Flies.^ Ontario Dept. 

 Agric. Toronto, Out., llvW. no. 227, January 1915, 30 pp., 18 figs. 



Rhagoletis cingidata, Lw., and R. fansta, 0. S., have been causing 

 much loss to cherry-growers in Ontario. They were not recognised 

 as pests until 1910 and 1912 respectively. The flies lay their eggs jusb 

 beneath the skin of the cherry and, on hatching, the larvae feed on 

 the juice and destroy the pulp. In infested orchards, the percentage 

 of wormy fiuit varies from 5 to 99. Infested fruits are subject to 

 brown rot and help to spread this disease. It is often almost impos- 

 sible to tell whether a cherry is infested or not until it is opened. So 

 far, the cherry is the only orchard fruit known to be subject to attack ; 



